The engine immobiliser system is designed to prevent the vehicle from being stolen. This system uses a transponder key ecu that stores the key codes of authorized ignition keys. If an attempt is made to start the engine using an unauthorized key, the ecu sends a signal to the ecm to prohibit fuel delivery and ignition, effectively disabling the engine.

The transponder key coil receives this signal, the transponder key amplifier amplifies it, and then the signal is transmitted to the ecu. The ecu matches the key's id code with the vehicle's id code, which was previously registered in the ecu and then communicates the results to the ecm using sfi communication.
Engine immobiliser system
How to proceed with troubleshootingOn-vehicle inspection
Check battery condition
Notice:
If the battery is weak or if the engine is difficult to
start, perform the following procedures.
Check the battery for damage and deformation. If
severe damage, deformation or leakage is found,
replace the battery.
Check the electrolyte quantity of e ...
Front passenger side seat belt warning light malfunction
Description
When the ignition switch is on, the center airbag sensor transmits front seat
inner belt status signals to
the combination meter through the can bus line. If the front passenger seat belt
is not fastened, the
heater control panel (automatic a/c) or clock (manual a/c) blinks the fr ...
Ig2 relay
On-vehicle inspection
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove ig2 relay
Remove the no. 1 Engine room re ...